Oil de-emulsifying process



Patented Oct. 6, 1936 ATET FFIQE on. DE-EMULSIFYING PROCESS No Drawing.Application June 2, 1936, Serial No. 83,173

11 Claims. (Cl. 196-4) This invention pertains to processes and reagentsfor de-emulsifying mineral oil emulsions, particularly petroleum andwater emulsions of all types including those having tendencies towardgreat stability by reason of the presence of saline and organicmaterials.

The general purpose of the invention is to provide a process forbreaking mineral oil emulsions, by the use of a new de-emulsifyingreagent capable of successfully treating the most stable of emulsions,and possessing certain high important advantages over reagentsheretofore used for the treatment of mineral oil emulsions. Outstandingamong these advantages is the ability of the present reagent, whenintimately admixed with the emulsion, to bring about separation of theoil and ,water in an unusually short period of time, and without thenecessity for agitation or heating of the emulsion. Of course, if forany reason it may be desired to agitate or heat the emulsion while it isbeing acted upon by the reagent, resort may be had to such expedients.But from all indications that have developed from the treatment ofvarious difierent emulsions, including highly stable forms and somecontaining high percentages of water in the presence of efiectiveemulsifying agents, neither agitation nor heatingare necessary.Consequently, I am able to eliminate the usual expense of heat ing theemulsion during treatment, and the costly loss of the lighter and morevolatile constituents of the oil that ordinarily are vaporized asa'result of heating or agitation.

In accordance with the invention, I utilize in the de-emulsifyingreagent one or more of certain types of water soluble salts that whenput into the emulsion, develop a high degree of ionization and destroyor render inefiective the emulsifying agent by reaction with the mineralsalts 40 therein to form compounds that, relatively at least, are waterinsoluble; At this point it may be mentioned that all the reasonsunderlying the action of the present reagent on the emulsion are notfully known, and that while for the purpose 5 of describing theinvention, certain explanations of a theoretical nature may be given, itis to be understood that these may be subject to modification in thelight of future determinations. The types of water soluble saltscontemplated by the invention for use in the reagent, are, generally,the thio salts, including the thio sulphates and the thio cyanates, ormixtures of those salts. It will be understood that any suitable salt ofeither type may be used, and that the selection of any particular saltor salts will depend upon the nature of the emulsion to be treated, andparticularly the characteristics of the emulsifying agent. I may cite astypical, and generally preferred thio salts, sodium, potassium orammonium thiosulphate and sodium, potassium or 5 ammonium thiocyanate.

This thio salt preferably is put into aqueous solution in suitableconcentration, say one pound of the salt in five gallons of water. Iinclude in the aqueous solution a compound or selected com- 10 binationof compounds, that together with the salt form an actuated and highlydispersible reagent having the capacity for thorough and rapiddistribution throughout the emulsion, and a corresponding capacity forrapid breakdown of the l5 emulsion phases. The last mentioned compoundor compounds (which may be termed distributing agents since they act todistribute or disperse the salt intimately throughout the emulsion) tobe used together with the thio salt, may be selected from two generalclasses of substances; the gly- 20 col ethers or the higher alcohols,including their isomers. Typical glycol ethers are diethylene glycolethers of the monomethyl, ethyl, propyl, etc., series. The higheralcohols include methyl, 25

ethyl, propyl and butyl alcohols and their isomers. In the treatment ofcertain emulsions it may also be desirable to include in the reagent,relatively small amounts of acetic or lactic acids, or both. When acombination of the thio salt 30 together with one or moreof the higheralcohols, with perhaps small amounts of lactic and acetic acids, is usedto make up the reagent, its composition in certain general respectsresembles that of a reagent prepared in accordance with the methoddisclosed in the copending application of George B. Bavin and MaxPowell, Ser. No. 78,894, filed on May 9, 1936. That application isdirected to a process of treating mineral oil emulsions by the use of areagent prepared by fer- 0 menting a solution to obtain a fermentationproduct containing the higher alcohols, and perhaps certain acids, andto which a suitable thio salt may be added for one purpose, amongothers, of activating the alcohols. 45

In preparing the tie-emulsifying reagent, the several ingredients may beproportioned within any suitable limits to give the best results for theparticular emulsion to be treated. Preferably, though not necessarily inall cases, the gly- 5o col ether or alcohol content of the reagent willbe proportioned to adjust the specific gravity of the thio saltsolution, to correspond closely to the specific gravity of the aqueousemulsion phase. When a glycol ether is used, I preferably 55 employ athiosulphate salt, usually sodium thiosulphate, in the reagent becauseof its relative cheapness and availability- A thiocyanate, e. g. sodiumor potassium thiocyanate, preferably is employed where an alcohol orcombination, of

alcohols are used instead of the glycol ether, because of thegreatersolubility of the thiocyanate in alcohol.; f' I ,1 1

.A typical reagent maybe made up in {the pro-' portions'of one pound ofsodium thiosulphate to 2.43pounds of diethylene glycol and41.6jpouncls',

or approximately ifive gallons, of water; In. any;

Composition, the proportion may vary within Wide limits dependinguponthefdilut'iondesired. As stated before, relatively small amounts,of; lactic and acetic acids may be added if desired.

In the process of subjectingfthe emulsion to the-action of the reagent,any'of the usual or suitable methods may be employed for securing i anintimate. admixture of the reagent with the Foriexample, where the oilis. flow-- ing directly from thewellintoastorage.or.;treatingstank-,.thegre a'gent mayabe injected atameasfured rate into the flow line withinwhich the reagent and emulsionare'intimately admixed.

and then discharged .into the tank wherein the: -:emulsion isjallowed tostand alength of time 'toienablethe' reagent to effectively andcompletes'uflicient' for the reagent to effectseparationof the "oilandilwater constituents oftheemulsion'.

1 Again, the emulsion may be put directly into the:

tahkar'rdtheieniulsion perhaps agitated to-what ever extent: may benecessary and until disper jfsion of the reagent. Beyond the mereadmixing:

'of the reagent-with the emulsion in the tank, no furthenop'erations'appear to; be necessary ly break the emulsion. Asi'observed.hereinabove;

the-present reagent appears to have" the: distihc tive characteristic ofnotrequiring that the emul-v s-ier'r be. subjected to' agitation;excepting for: mere admixing; or heating: during the treating; period.The effectiveness 'of the reagent'to break" emulsions within anunusually short period. of time, has been evidenced by past operationslin'.

the treatment of five hundred. barrel lots of oils In-a typical runytheoil was discharged into,-tl1'e.--

'treati-ng tank; over a period of hours,: during. which} aroundthree-gallons of' the reagent was injectedinto'the fiow' line-ata slowuniform rate; The emulsion; containing 'ahigh percentage of water; wasthenallowedi to stand forabouttvvelve:-

u hours, at the end of which time the water was' drained ofigan'di theremaining :oil tested forwa-'- found to be'less'than 0.6%.

'ter. The watercontentofi the treated;v oil was 55; v V For the purposeof iurtheriascertaining' the effectiveness or thei-de-emul'sifyingreagent; the

treated oil was allowed 'to remain in the tank and a several hundredbarrels of emulsion/coming; di. rectly from thewelland unmixed withadditional reagent, were pumped into the tank and mixed withthepre'viously'dehydratedoil. After about twelve hours andwithoutlfurthe'r reagent being added, the water was drained from thetank-and;

the remaining oil tested for water'. The water:

I claim:

1. The method of treating crude petroleum emulsions that includessubjecting the emulsion to the action of a reagent comprising an aqueousthio salt solution, and a distributing agent dis- 7 solved in saidsolution and acting to disperse said salt throughout the emulsion.

2. The. method of treating crude petroleum emulsions that includessubjecting the emulsion to the action of a-reagent comprising an aqueousthio salt solution, and a distributing agent dissolvedin said solutionand acting to disperse said salt throughout the emulsion, the volume ofwater being substantially in excess of the volume of the distributingagent.

3. The method of treating crude petroleum emulsions. that, includessubjecting the emulsion text-he action of a reagent comprising anaqueous thio salt solution, a distributing agent dissolved insaidsolution and acting to disperse said salt throughout theaemulsion,and an acid.

4-..ITha1meth0di of. treating crude. petroleum emulsionsi that'includessubjecting: the emulsion to the. actioniof a. reagent comprising. anaqueous:

thiosulphatelixsalt: solution, and. a distributing agent dissolved insaid; solution and acting to disperse :said salt throughout theemulsion.

' 5; The m'etho'd of: treating crude: petroleum emulsionssthagt;includes subjecting the: emulsion ti: thElaCtiOll-Of 'aire'agentcomprising an aqueous thiocyanata salt scluti'onandsa distributing agentdissolved saidsoluti'on and acting: to disperse said salt; throughoutthe emulsion.

Theti ihthod {of' treating crude petroleum emulsions i-thatincludesi'subjecting the emulsion;

tothez'aetiorr of areagent comprising-an aqueous thicxbsalttsolutiom.and a glycol ether dissolved in said solution.

7 The method of 'treating crude petroleum emulsions that'includessubjecting the emulsion to; theaction'of a reagent comprising an aqueoustl iio-sal t solutiong and a water soluble alcohol disselve' d insaidsolution. 7

8-.Themethod'ef treating-crudepetroleumemulsions. that" includessubjecting the emulsion t'o-the action-or 'a'solut-ion containing awatersoluble thiosulphateesalt dissolved in a distributing-agent actingto' disperse the salt throughout the emulsion. 7

9': 'Ihemethod'of treating crude petroleum:

emulsions that includes' subjecting the" emulsion to the actionof asolution containing a water solub e thiosulphat salt-dissolved in'alycol eth acting to disperse the salt throughout the emulsion.

w '10.. The. method efftreating crude petroleum emulsions that includes.subjecting the emulsion to the actionof'a reagentlcomprising an aqueousthiosulphate solution, and a diethylene glycol ether as umed insaidsolutien- 1:1. 'Lhe I method of treating crude petroleumemulsions thatincludes subjecting the emulsion ta the action of, a'reagent-comprisingan aqueous thiosulphatesolution. and a-diethylene glycol ether,thevolurhe of water being; substan.-

'tially inexeesswoi. the volume of the diethyleneglyeolsethem MAXPOWELL.

